The invention relates to a mechanism for transporting the leading end of a staple wire from a supply roll to a stapling device for sheet stacks via a guide tube for the staple wire arranged between the staple wire supply roll and the stapling device, such mechanism having a movable holder on which the staple wire supply roll is mounted, the holder with the staple wire supply spool being movable between a position arranged inside an apparatus and a position projecting beyond the outside of the apparatus.
In the case of a mechanism of the type disclosed by U.S. Pat. No. 4,898,314, the staple wire is arranged in a cassette, and a flexible guide tube, which is joined to the cassette and whose outlet is configured as a coupling to which the wire end is attached, is provided. The staple wire is joined by means of said coupling to a wire transport mechanism, arranged in the region of the stapling device, which transports the staple wire into the stapling device. With this known mechanism, a complete unit consisting of a cassette, a guide tube, and a coupling must be replaced each time the supply of staple wire is to be replenished. When a new supply of staple wire is inserted, the coupling joined to it must be moved manually to the immediate vicinity of the stapling device.
In another mechanism for transporting the leading end of the wire to a stapling device (U.S. Pat. No. 4,722,467), a threading-in mechanism which has a funnel-shaped inlet opening for the wire end is provided directly upstream from the stapling device. The wire end is introduced manually into said inlet opening, and pushed forward until the leading end arrives at visible marks, from which point wire transport on the part of the stapling device becomes effective. At the beginning of the threading-in process, a clamping mechanism for the wire must be moved manually into an ineffective position, and, once the threaded-in position is reached, must be moved into a clamping position which prevents the staple wire from slipping back.
In the case of a loading mechanism for a staple wire roll disclosed in Research Disclosure No. 29834, May 1988, a displaceable holder is provided on which the staple wire roll is mounted. The holder is movable from a location arranged inside an apparatus into a pulled-out location in which the staple wire roll is positioned to be accessible for replacement. With this mechanism, the leading end of the staple wire must be pushed manually into a flexible tube leading to a transport mechanism of a stapling head until the leading wire end has arrived at the transport mechanism.
With these known and in some cases relatively complex mechanisms, it is necessary to transport the wire end by hand to the immediate vicinity of the stapling device. Since the stapling device of a stapling apparatus, which can for example be arranged in a finisher for folding, collating, stapling, and depositing sheet stacks, is as a rule arranged at a poorly accessible point in the apparatus, replenishing the staple wire supply is, with the known devices, so complex and laborious that it can be performed only by trained personnel.